Thixotropic polyurethane systems

• US 5,338,767 A
• Filed: 03/19/1993
• Issued: 08/16/1994
• Est. Priority Date: 07/19/1990
• Status: Expired due to Term

• Current Assignee: Henkel KGaA (Henkel AG & Co KGaA)
• Original Assignee: Henkel KGaA (Henkel AG & Co KGaA)
• Inventors: Aggias, Zissis, Sanch, Francois R., Sartelet, Jean-Francois
• Primary Examiner(s): WELSH JR, MAURICE
• Application Number:
  US07/969,814
• Time in Patent Office: 515 Days
• Field of Search: 521/159, 521/163, 521/166, 528/59, 528/60, 528/61, 528/62, 528/73, 528/74.5
• US Class Current: 521/159
• CPC Class Codes: C08G 18/0885 using additives, e.g. absorbing agents
• CPC Class Codes: C08G 18/4054 Mixtures of compounds of group C08G18/60 with other macromolecular compounds
• CPC Class Codes: C08G 18/6529 Compounds of group C08G18/3225 or polyamines of C08G18/38
• CPC Class Codes: C08G 18/6547 the low-molecular compounds being compounds of group C08G18/36 or hydroxylated esters of higher fatty acids of C08G18/38
• CPC Class Codes: C09J 175/04 Polyurethanes

Abstract

Thixotropic polyurethane systems based on a polyol component and an isocyanate component, the polyol component containing a mixture of polyamidoamine and low molecular weight, polyfunctional amines, more particularly aromatic amines, which are suitable in particular as adhesive systems for special applications.

Claims

1. A polyurethane system comprising a polyol component and a polyisocyanate component resin wherein said polyol component is comprised of a mixture of at least one polyamidoamine and at least one low molecular weight polyfunctional amine.

2. The polyurethane system according to claim 1 wherein said low molecular weight polyfunctional amine is an aromatic amine.

3. The polyurethane system according to claim 1 wherein the weight ratio of said low molecular weight polyfunctional amine to said polyamidoamine is from about 10:

1 to about 2;

3.

4. The polyurethane system according to claim 3 wherein said weight ratio is from about 2:

1 to about 4;

1.

5. The polyurethane system according to claim 1 wherein the total of the weight percent of said low molecular weight polyfunctional amine and said polyamidoamine is from about 1% to about 10%.

6. The polyurethane system according to claim 5 wherein said weight percent is from about 2 to about 6%.

7. The polyurethane system according to claim 1 wherein said low molecular weight polyfunctional amine is a diamine.

8. The polyurethane system according to claim 7 wherein said diamine is a cycloaliphatic diamine.

9. The polyurethane system according to claim 7 wherein said diamine is polyoxypropylene α

,ω

-diamine.

10. The polyurethane system according to claim 1 wherein said low molecular weight polyfunctional amine is an alkanolamine which is a liquid at room temperature.

11. The polyurethane system according to claim 1 wherein said low molecular weight polyfunctional amine is tetramethyl ethylenediamine.

12. The polyurethane system according to claim 1 wherein said low molecular weight polyfunctional amine is an aromatic diamine.

13. The polyurethane system according to claim 12 wherein said aromatic diamine is 2,4-diaminomesitylene;

1,3,5-triethyl-2,4-diaminobenzene;

1,3,5-triisopropyl-2,4-diaminobenzene;

4,6-dimethyl-2-ethyl-1,3-diaminobenzene;

3,5,3'"'"',5'"'"'-tetraethyl-4,4'"'"'-diaminodiphenylmethane;

3,5,3'"'"',5'"'"'-tetraisopropyl-4,4'"'"'-diaminodiphenylmethane;

3,5-diethyl-3'"'"',5'"'"'-diisopropyl-4,4'"'"'-diaminodiphenylmethane;

1-t-butyl-3,5-dimethyl-2,4-diaminobenzene;

1-t-butyl-3,5-dimethyl-2,6-diaminobenzene.

14. The polyurethane system according to claim 12 wherein said aromatic diamine is a trialkyl-substituted diaminobenzene.

15. The polyurethane system according to claim 14 wherein said trialkyl-substituted diaminobenzene is a mixture of isomers having one methyl and two ethyl groups.

16. The polyurethane system according to claim 15 wherein said mixture of isomers is comprised of 1-methyl-3,5-diethyl-2,4-diaminobenzene;

1-methyl-3,5-diethyl-2,2-diaminobenzene;

or a combination thereof.

17. The polyurethane system according to claim 1 wherein said polyamidoamine is the reaction product of an oligomerized fatty acid and an excess of a polyfunctional amine.

18. The polyurethane system according to claim 17 wherein said oligomerized fatty acid is a trimmer fatty acid.

19. The polyurethane system according to claim 1 wherein said polyamidoamine is the reaction product of an oligocarboxylic acid obtained from the oligomerization of an unsaturated fatty acid wherein said oligocarboxylic acid is comprised of at least 50% by weight of trimmer fatty acid, from about 10% to about 50% by weight of dimer fatty acid, and from 0 to about 2% by weight of monomeric fatty acid with an excess of heterocyclic diamine of the formula ##STR2## wherein R is hydrogen, or R'"'"'NH₂ wherein R'"'"' is a saturated aliphatic hydrocarbon chain.

20. The polyurethane system according to claim 19 wherein said aliphatic hydrocarbon chain is a --C₂ H₄ -- group.

21. The polyurethane system according to claim 1 wherein the said polyamidoamine has an average molecular weight of about 1,200 and an empirical formula of C₇₂ H₁₅₀ N₉ O₃.

22. The polyurethane system according to claim 1 wherein the said polyamidoamine has a viscosity of about 3,000 Pa at 25°

C.

23. A process for producing a polyurethane comprising the steps of:

(1) adding a polyfunctional amine and a polyamidoamine to a polyol to form a polyol component;

(2) mixing said polyol component and an isocyanate component.